I've made a program to find the missing element (if there's one) in a sequential list:

Program criteria:

Returns -1 if a list is sequential, otherwise the missing element in a non-sequential list is returned.

To perform binary search, we need a key to half the problem size. Here the key is to find the distance between the index (low, high) and their corresponding values.

Compilation procedure:

gcc -Wall -g testList.c -o testList

./testList

#include<stdio.h>
int bSearch(int array[], int low, int high){
 int mid = (low + high) / 2;
 if(high == low + 1){
 if(array[high] > array[low] +1){
 return array[low] +1;
 }else{
 return -1;
 }
 }
 if(array[mid] - array[low] == mid - low){
 return bSearch(array, mid, high);
 }else if(array[mid] - array[low] > mid - low){
 return bSearch(array, low, mid);
 }else{
 return -1;
 }
}
int main(void){
 int array [] = {22, 23, 24, 25, 26, 27, 28, 30};
 int upperBound = (sizeof(array)/sizeof(array[0]))-1;
 printf("%d\n", bSearch(array, 0, upperBound));
 return 0;
}

My questions:

1. Why does removing the else{} case cause the compiler to give a warning for it?

2. Can the base case look more elegant?

3. For code elegance and optimization, can this code be improved?

I've made a program to find the missing element (if there's one) in a sequential list:

Program criteria:

Returns -1 if a list is sequential, otherwise the missing element in a non-sequential list is returned.

To perform binary search, we need a key to half the problem size. Here the key is to find the distance between the index (low, high) and their corresponding values.

Compilation procedure:

gcc -Wall -g testList.c -o testList
./testList

#include<stdio.h>
int bSearch(int array[], int low, int high){
 int mid = (low + high) / 2;
 if(high == low + 1){
 if(array[high] > array[low] +1){
 return array[low] +1;
 }else{
 return -1;
 }
 }
 if(array[mid] - array[low] == mid - low){
 return bSearch(array, mid, high);
 }else if(array[mid] - array[low] > mid - low){
 return bSearch(array, low, mid);
 }else{
 return -1;
 }
}
int main(void){
 int array [] = {22, 23, 24, 25, 26, 27, 28, 30};
 int upperBound = (sizeof(array)/sizeof(array[0]))-1;
 printf("%d\n", bSearch(array, 0, upperBound));
 return 0;
}

My questions:

1. Why does removing the else{} case cause the compiler to give a warning for it?

2. Can the base case look more elegant?

3. For code elegance and optimization, can this code be improved?

I've made a program to find the missing element (if there's one) in a sequential list:

Program criteria:

Returns -1, if, list is sequential otherwise missing element in non-sequential list is returned.

To perform binary search, we need a key to half the problem size. Here the key is, to find the distance between the index (low, high) and their corresponding values.

Compilation procedure

gcc -Wall -g testList.c -o testList

./testList

#include<stdio.h>
int bSearch(int array[], int low, int high){
 int mid = (low + high) / 2;
 if(high == low + 1){
 if(array[high] > array[low] +1){
 return array[low] +1;
 }else{
 return -1;
 }
 }
 if(array[mid] - array[low] == mid - low){
 return bSearch(array, mid, high);
 }else if(array[mid] - array[low] > mid - low){
 return bSearch(array, low, mid);
 }else{
 return -1;
 }
}
int main(void){
 int array [] = {22, 23, 24, 25, 26, 27, 28, 30};
 int upperBound = (sizeof(array)/sizeof(array[0]))-1;
 printf("%d\n", bSearch(array, 0, upperBound));
 return 0;
}

My questions:

1. Why does removing the else{} case cause the compiler to give a warning for it?

2. Can the base case look more elegant?

3. For code elegance and optimization, can this code be improved?

I've made a program to find the missing element (if there's one) in a sequential list:

Program criteria:

Returns -1 if a list is sequential, otherwise the missing element in a non-sequential list is returned.

To perform binary search, we need a key to half the problem size. Here the key is to find the distance between the index (low, high) and their corresponding values.

Compilation procedure:

gcc -Wall -g testList.c -o testList

./testList

#include<stdio.h>
int bSearch(int array[], int low, int high){
 int mid = (low + high) / 2;
 if(high == low + 1){
 if(array[high] > array[low] +1){
 return array[low] +1;
 }else{
 return -1;
 }
 }
 if(array[mid] - array[low] == mid - low){
 return bSearch(array, mid, high);
 }else if(array[mid] - array[low] > mid - low){
 return bSearch(array, low, mid);
 }else{
 return -1;
 }
}
int main(void){
 int array [] = {22, 23, 24, 25, 26, 27, 28, 30};
 int upperBound = (sizeof(array)/sizeof(array[0]))-1;
 printf("%d\n", bSearch(array, 0, upperBound));
 return 0;
}

My questions:

1. Why does removing the else{} case cause the compiler to give a warning for it?

2. Can the base case look more elegant?

3. For code elegance and optimization, can this code be improved?